TW201546619A - Dongle for electronic apparatus - Google Patents

Abstract

A dongle for an electronic apparatus including a first connector, a second connector, a power bus, a switch circuit and a detecting circuit is provided. The first connector connects to the connector of the electronic apparatus. The second connector selectively connects to an external power supply. The power bus is coupled to the first power pin of the first connector and the first terminal of the switch circuit. The second terminal of the switch circuit is coupled to the second power pin of the second connector. The conduction state of the switch circuit is dependent on whether the second power pin receives the power of the external power supply. The detecting circuit detects whether the second power pin receives the power of the external power supply, and sends a stop-powering signal to the identification pin of the first connector. The identification pin transmits the stop-powering signal to the connector of the electronic apparatus.

Description

Electronic device adapter

The present invention relates to an adapter for an electronic device.

Existing portable electronic devices (such as tablet or mobile phones) generally have a Universal Serial Bus (hereinafter referred to as USB) On-The-Go (OTG) connector. USB OTG is a supplement to the USB 2.0 specification. When the USB OTG connector is connected to a peripheral device such as a USB flash drive, mouse or keyboard, the portable electronic device plays the role of a host. When the USB OTG connector is connected to another USB host (such as a computer, a laptop, etc.) or a power adapter, the portable electronic device can be switched from the host role to the peripheral device role.

1 and 2 are schematic diagrams illustrating the USB connector 110 of the electronic device 100 for plugging/unplugging a power adapter 10 or a dongle 20. The adapter 20 can be a TV donggle, a Bluetooth USB dongle, a WiFi USB dongle, or other adapter. Referring to FIG. 1, the electronic device 100 has a connector 110, wherein the connector 110 can be a USB OTG connector. The user can place the power adapter 10 The connector 12 is inserted into the connector 110 of the electronic device 100. When the connector 12 of the power adapter 10 is inserted into the connector 110 of the electronic device 100, the power adapter 10 can provide power 11 to the electronic device 100 via the connector 12 and the connector 110 to charge and power the electronic device 100. Since the connector 110 has been occupied by the power adapter 10, other peripheral devices (such as the adapter 20) cannot be inserted into the connector 110. To insert the connector 22 of the adapter 20 into the connector 110, the user must first pull the connector 12 of the power adapter 10 out of the connector 110.

Referring to FIG. 2, after the user pulls out the connector 12 of the power adapter 10 from the connector 110, the connector 22 of the adapter 20 can be inserted into the connector 110. When the connector 22 of the adapter 20 is inserted into the connector 110, the electronic device 100 can provide power 111 to the adapter 20 via the connector 22 and the connector 110 to power the adapter 20. The material 112 can be transferred between the adapter 20 and the electronic device 100 via the connector 22 and the connector 110. Since the connector 110 has been occupied by the adapter 20, the connector 12 of the power adapter 10 cannot be inserted into the connector 110. To charge and power the electronic device 100 using the power adapter 10, the user must first unplug the connector 22 of the adapter 20 from the connector 110.

As described above with respect to FIGS. 1 and 2, since the connector 110 has been occupied by one of the adapter 20 and the power adapter 10, the other of the power adapter 10 and the power adapter 10 cannot be inserted into the connector 110. Furthermore, the user must frequently plug and unplug the connector 110 of the electronic device 100 to selectively connect the power adapter 10 or the adapter 20. Frequent insertion and removal will accelerate the wear of the connector 110.

The present invention provides a dongle for an electronic device to dynamically change the power supply relationship between the electronic device and the adapter.

The adapter of the embodiment of the present invention includes a first connector, a second connector, a power bus, a transmission module, a switch circuit, and a detection circuit. The first connector is selectively electrically connectable to the connector of the electronic device. The power bus is coupled to the first power pin of the first connector. The second connector is selectively electrically connectable to the external power supply. The transmission module has a third power pin coupled to the power bus. The first end and the second end of the switch circuit are respectively coupled to the power bus and the second power pin of the second connector. The second end is capable of receiving the second switching signal output by the second power pin to make the switching circuit be in an on state, and the external power supply output power is transmitted to the power bus via the second power pin and the switching circuit, and is capable of transmitting power through the power The row transmits power to the first power pin and the third power pin. The output end and the detecting end of the detecting circuit are respectively coupled to the identification pin of the first connector and the second power pin. The detecting end can receive the first switching signal output by the second power pin to make the detecting circuit be in an off state, when the first connector is electrically connected to the connector of the electronic device and the second connector is electrically connected to the external power supplier The identification pin transmits a connector that stops the power transmission signal to the electronic device according to the off state.

In an embodiment of the invention, when the connector of the electronic device receives the stop power transmission signal for identifying the pin transmission, the connector of the portable electronic device changes the power operation of the controller of the connector of the electronic device according to the stop power transmission signal. mode.

In an embodiment of the invention, the connector of the electronic device is The controller is a Universal Serial Bus (USB) connector. The controller of the connector is a Universal Serial Bus (USB) controller.

In an embodiment of the invention, when the second connector is not electrically connected to the external power supply, the connection state between the first end and the second end of the switch circuit is an off state, and the detection circuit is in an on state. The power operation mode of the controller of the connector of the electronic device is an On-The-Go (OTG) mode.

In an embodiment of the invention, when the second connector is electrically connected to the external power supply, the connection state between the first end and the second end of the switch circuit is an on state, and the detection circuit is in an off state. The connector of the electronic device receives the stop power transmission signal for identifying the pin transmission, so that the connector changes the power operation mode of the controller from the connection mode, that is, the auxiliary charging adapter (ACA) mode according to the stop power transmission signal.

In an embodiment of the invention, the detecting circuit further includes a first switch. The first end of the first switch is coupled to the identification pin of the first connector, the second end of the first switch is coupled to the reference voltage, and the control end of the first switch is coupled to the second power of the second connector Pin.

In an embodiment of the invention, the detecting circuit further includes a pull-down resistor. The first end and the second end of the pull-down resistor are respectively coupled to the identification pin of the first connector and the reference voltage.

In an embodiment of the invention, the switching circuit is a second switch. The first end of the second switch is coupled to the power bus, and the second end of the second switch is The control end is coupled to the second power pin.

In an embodiment of the invention, the switching circuit includes a first P-type transistor, a second P-type transistor, a first capacitor, a first resistor, a second resistor, an N-type transistor, and a control circuit. The first end of the first P-type transistor is coupled to the power bus. The first end of the second P-type transistor is coupled to the second end of the first P-type transistor, and the second end of the second P-type transistor is coupled to the second power pin. The first end of the first capacitor is coupled to the second end of the first P-type transistor and the first end of the second P-type transistor, and the second end of the first capacitor is coupled to the first P-type transistor The control end is connected to the control end of the second P-type transistor. The first end of the first resistor is coupled to the second end of the first P-type transistor and the first end of the second P-type transistor, and the second end of the first resistor is coupled to the first P-type transistor The control end is connected to the control end of the second P-type transistor. The first end of the second resistor is coupled to the second end of the first resistor. The first end of the N-type transistor is coupled to the second end of the second resistor, and the second end of the N-type transistor is coupled to the reference voltage. The control circuit is coupled to the control terminal of the N-type transistor. The control circuit correspondingly controls the N-type transistor according to the voltage of the second power pin.

In an embodiment of the invention, the detecting circuit includes a first sub-switch, a second sub-switch, and a pull-down resistor. The first end of the first sub-switch is coupled to the identification pin of the first connector. The second end of the first sub-switch is coupled to the reference voltage. The control end of the first sub-switch is coupled to the second power pin of the second connector. The first end of the second sub-switch is coupled to the identification pin of the first connector. The control end of the second sub-switch is coupled to the first end of the second resistor. The first end and the second end of the pull-down resistor are respectively coupled to the second end of the second sub-switch and the reference voltage.

In an embodiment of the invention, the control circuit includes a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a second capacitor, an operational amplifier, a seventh resistor, an eighth resistor, and a third capacitor. The first end of the third resistor is coupled to the second power pin. The first end and the second end of the fourth resistor are respectively coupled to the second end of the third resistor and the reference voltage. The first end of the fifth resistor is coupled to the second power pin. The first end and the second end of the sixth resistor are respectively coupled to the second end of the fifth resistor and the reference voltage. The first end and the second end of the second capacitor are respectively coupled to the second end of the fifth resistor and the reference voltage. The first input end and the second input end of the operational amplifier are respectively coupled to the second end of the third resistor and the second end of the fifth resistor. The first end and the second end of the seventh resistor are respectively coupled to the output end of the operational amplifier and the control end of the N-type transistor. The first end and the second end of the eighth resistor are respectively coupled to the second end of the seventh resistor and the reference voltage. The first end and the second end of the third capacitor are respectively coupled to the second end of the seventh resistor and the reference voltage.

In an embodiment of the invention, the first connector further includes a first data pin, and the transmission module further includes a third connector. The third connector has a third power pin and a second data pin. The third power pin of the third connector is coupled to the power bus. The second data pin of the third connector is coupled to the first data pin of the first connector. The third connector is selectively electrically connectable to the peripheral device of the electronic device.

In an embodiment of the invention, the adapter further includes a clamping circuit. The clamp circuit is coupled to the first data pin of the first connector. The clamping circuit will first connect the first connector when the second connector receives the power of the external power supply The potential of the first data pin is maintained at the first potential.

Based on the above, depending on whether the adapter receives power from the external power supply, the adapter of the embodiment of the present invention can dynamically change the power supply relationship between the electronic device and the adapter. When the adapter receives power from the external power supply, the power of the external power supply can supply power to the electronic device and the adapter. When the adapter does not receive power from the external power supply, the electronic device can supply power to the adapter.

The above described features and advantages of the invention will be apparent from the following description.

10‧‧‧Power Adapter

11‧‧‧Power

12‧‧‧Connector

20‧‧‧Adapter

22‧‧‧Connector

30‧‧‧External power supply

31‧‧‧Power

32‧‧‧Connector

40‧‧‧ Peripheral devices

41‧‧‧Connector

100‧‧‧Electronic devices

110‧‧‧Connector

111‧‧‧Power

112‧‧‧Information

300‧‧‧Adapter

310‧‧‧First connector

320‧‧‧Second connector

330‧‧‧Detection circuit

331‧‧‧First switch

332‧‧‧ Pull-down resistor

333‧‧‧First sub-switch

334‧‧‧Second sub-switch

335‧‧‧ Pull-down resistor

340‧‧‧Switch circuit

341‧‧‧second switch

350‧‧‧Transmission module

351‧‧‧ Third connector

1011‧‧‧resistance

1012‧‧‧Solid relay

1021‧‧‧First P-type transistor

1022‧‧‧Second P-type transistor

1023‧‧‧first capacitor

1024‧‧‧first resistance

1025‧‧‧second resistance

1026‧‧‧N type transistor

1030‧‧‧Control circuit

1031‧‧‧ Third resistor

1032‧‧‧fourth resistor

1033‧‧‧ fifth resistor

1034‧‧‧6th resistor

1035‧‧‧second capacitor

1036‧‧‧Operational Amplifier

1037‧‧‧ seventh resistor

1038‧‧‧8th resistor

1039‧‧‧ third capacitor

1100‧‧‧Clamp circuit

1101‧‧‧resistance

1102‧‧‧resistance

D_pad‧‧‧First data pin

DM_pad‧‧‧ first sub-data pin

DP_pad‧‧‧ first sub-data pin

D_dev‧‧‧Second data pin

DM_dev‧‧‧Second sub-data pin

DP_dev‧‧‧Second sub-data pin

ID_pad‧‧‧ID pin

V_chg‧‧‧second power pin

V_dev‧‧‧ third power pin

V_pad‧‧‧First power pin

VBUS‧‧‧Power Bus

1 and 2 are schematic diagrams illustrating a USB connector plug/unplug power adapter or a dongle of an electronic device.

FIG. 3 and FIG. 4 are schematic diagrams showing different scenarios in which an adapter is plugged into an electronic device according to an embodiment of the invention.

FIG. 5 is a block diagram showing the circuit of the adapter shown in FIG. 3 and FIG. 4 according to an embodiment of the invention.

6 and FIG. 7 are schematic diagrams illustrating an embodiment of the adapter shown in FIG. 5, and an operation of the adapter in different scenarios.

8 and FIG. 9 are schematic diagrams showing different scenarios in which an adapter is plugged into an electronic device according to another embodiment of the present invention.

FIG. 10 is a block diagram showing the circuit of the adapter shown in FIG. 8 and FIG. 9 according to another embodiment of the present invention.

FIG. 11 is a block diagram showing the circuit of the adapter shown in FIG. 8 and FIG. 9 according to still another embodiment of the present invention.

FIG. 12 is a block diagram showing the circuit of the clamp circuit of FIG. 11 according to an embodiment of the invention.

The term "coupled" as used throughout the specification (including the scope of the patent application) may be used in any direct or indirect connection. For example, if the first device is described as being coupled to the second device, it should be construed that the first device can be directly connected to the second device, or the first device can be connected through other devices or some kind of connection means. Connected to the second device indirectly. In addition, wherever possible, the elements and/ Elements/components/steps that use the same reference numbers or use the same terms in different embodiments may refer to the related description.

FIG. 3 and FIG. 4 are schematic diagrams illustrating different scenarios in which the dongle 300 is plugged into the electronic device 100 according to an embodiment of the invention. The electronic device 100 shown in FIG. 3 and FIG. 4 can refer to the related description of the electronic device 100 in FIGS. 1 and 2. The adapter 300 shown in FIG. 3 and FIG. 4 can be a universal serial bus HUB (USB HUB), a TV donggle, a Bluetooth USB dongle. , wireless local area network USB adapter (WiFi USB dongle) or other adapters.

Referring to FIG. 3 , the first connector 310 of the adapter 300 is selectively electrically connected to the connector 110 of the electronic device 100 . The user can insert the first connector 310 of the adapter 300 into the connector 110 of the electronic device 100. In this embodiment, the first connector 310 can be, but is not limited to, an On-The-Go (OTG) connector. When the first connector 310 of the adapter 300 is inserted into the connector 110 of the electronic device 100, the data 112 can be transferred between the adapter 300 and the electronic device 100 via the first connector 310 and the connector 110. In a case where the second connector 320 of the adapter 300 does not receive the power of the external power supplier, the electronic device 100 may provide the power 111 to the adapter 300 via the connector 110 and the first connector 310 to be reversed. The connector 300 performs power supply.

Referring to FIG. 4, the second connector 320 is selectively electrically connected to the external power supply 30. In this embodiment, the second connector 320 and the connector 32 may be, but are not limited to, a general USB connector, a USB OTG connector, or other power connectors. The user can insert the connector 32 of the external power supply 30 into the second connector 320 of the adapter 300. In this embodiment, the external power supply 30 can be, but is not limited to, a power adapter, a mobile power source, or other power supply. In other embodiments, the external power supply 30 may be a personal computer, laptop, or other electronic device that can supply power.

When the connector 32 of the external power supply 30 is inserted into the second connector 320 of the adapter 300, the external power supply 30 can provide power 31 to the adapter 300 via the connector 32 and the connector 320. When the adapter 300 receives an external power In the case of the power 31 of the power supply 30, the power 31 of the external power supply 30 can be further transmitted to the electronic device 100 via the first connector 310 and the connector 110 in addition to the power supply to the adapter 300. Therefore, the power 31 of the external power supplier 30 can charge and power the electronic device 100. As shown in FIG. 4 , the user can simultaneously couple the adapter 300 and the external power supply 30 to the same connector 110 of the electronic device 100 .

FIG. 5 is a block diagram showing the circuit of the adapter 300 shown in FIG. 3 and FIG. 4 according to an embodiment of the invention. The adapter 300 includes a first connector 310, a second connector 320, a detection circuit 330, a switch circuit 340, a power bus VBUS, and a transmission module 350. The transmission module 350 represents an element such as an internal circuit, a component, a chip, and/or a connector of the adapter 300 that needs to receive power to operate. For example, in some embodiments, the transmission module 350 may include a USB control chip or a USB HUB wafer. In other embodiments, the transmission module 350 may include a wireless area network chip (eg, a WiFi chip) or other functional wafer. In other embodiments, the transmission module 350 may include a third connector for connecting to a peripheral device (eg, a USB flash drive, a mouse, or a keyboard). Referring to FIG. 6 and FIG. 7 together, the third power pin V_dev of the transmission module 350 is coupled to the power bus line VBUS. The data pin of the transmission module 350 is coupled to the first data pin D_pad of the first connector 310.

The first connector 310 has a first power pin V_pad and an identification pin ID_pad. The power bus bar VBUS is coupled to the first power pin V_pad of the first connector 310. The second connector 320 has a second power pin V_chg, wherein the second connector 320 is selectively electrically connectable to the external power supply 30, when the second connector When the external power supply 30 is electrically connected to the external power supply 30, the second power pin V_chg outputs a first switch signal and a second switch signal.

The first end of the switch circuit 340 is coupled to the power bus bar VBUS, and the second end of the switch circuit 340 is coupled to the second power pin V_chg of the second connector 320. The conduction state of the switch circuit 340 is dependent on the second power pin V_chg of the second connector 320 for receiving the power 31 of the external power supplier 30. For example, when the second power pin V_chg of the second connector 320 does not receive the power 31 of the external power supplier 30, the connection state between the first end and the second end of the switch circuit 340 is an off state (not When the second power pin V_chg of the second connector 320 is electrically connected to the external power supplier 30, the second end can receive the second switch signal output by the second power pin V_chg to make the switch circuit 340 The conduction state (ie, the connection state between the first end and the second end of the switch circuit 340 is an on state), and the external power supply 30 outputs a power 31 to the power convergence via the second power pin V_chg and the switch circuit 340. The VBUS is discharged, and the power 31 can be transmitted to the first power pin V_pad and the third power pin V_dev through the power bus bar VBUS.

The output of the detection circuit 330 is coupled to the identification pin ID_pad of the first connector 310. The detecting end of the detecting circuit 330 is coupled to the second power pin V_chg of the second connector 320. The detecting end can receive the first switching signal outputted by the second power pin V_chg to make the detecting circuit 330 be in an off state. When the first connector 310 is electrically connected to the connector 110 of the electronic device 100 and the second connector 320 is electrically connected When the external power supply 30 is connected, the identification pin ID_pad transmits a stop according to the cutoff state. The electrical signal is sent to the connector 110 of the electronic device 100.

Referring to FIG. 4 and FIG. 5, when the connector 32 of the external power supply 30 is inserted into the second connector 320 of the adapter 300, the connector 110 of the electronic device 100 receives the identification pin ID_pad of the first connector 310. The transmitting power transmission stop signal and the power operation mode of the controller (not shown) of the connector 110 of the electronic device 100 are changed according to the stop power transmission signal. The external power supply 30 can provide power 31 to the adapter 300 via the connector 32 and the connector 320. When the second connector 320 is electrically connected to the external power supply 30, the second power pin V_chg outputs the first switch signal and the second switch signal to the detection end of the detection circuit 330 and the second switch circuit 340, respectively. end. The first switch signal causes the detection circuit 330 to be in an off state, and the identification pin ID_pad transmits the controller (not shown) that stops the power transmission signal to the connector 110 of the electronic device 100 according to the detection circuit 330 being in an off state. . The second switch signal causes the switch circuit 340 to be in an on state, and the external power supply 30 output power 31 is transmitted to the power bus bar VBUS via the second power pin V_chg and the switch circuit 340, and the power bus bar VBUS can transmit the power 31 again. The first power pin V_pad and the third power pin V_dev of the transmission module 350 (please refer to FIG. 6 and FIG. 7 together). When the power transmission stop signal indicates that the second connector 320 receives the power 31 of the external power supply 30, the power operation mode of the controller (not shown) is set to the Accessory Charger Adapter (ACA) mode. In other words, the connector 110 of the electronic device 100 receives the stop power transmission signal transmitted by the identification pin ID_pad, so that the connector 110 operates the power operation mode of the controller (not shown) according to the stop power transmission signal (On -The-Go, Jane The OTG mode is changed to the ACA mode. In the ACA mode, the electronic device 100 can receive the power 31 of the external power supplier 30 via the second connector 320, the switch circuit 340, the power bus bar VBUS, the first connector 310, and the connector 110.

Referring to FIG. 3 and FIG. 5, when the second connector 320 is not electrically connected to the external power supplier 30, the connection state between the first end and the second end of the switch circuit 340 is an off state, and the detecting circuit 330 In a conducting state, a controller (not shown) that triggers the connector 110 of the electronic device 100 changes its power operation mode. For example, when the detecting circuit 330 is in an on state, indicating that the second connector 320 does not receive the power 31 of the external power supplier 30, the power operation of the controller (not shown) of the connector 110 of the electronic device 100 is performed. The mode is the On-The-Go (OTG) mode. In the OTG mode, the electronic device 100 can supply the power 111 to the power bus bar VBUS of the adapter 300 via the connector 110 and the first connector 310 to supply power to the power pin of the transmission module 350. At the same time, the switch circuit 340 is in an off state to prevent the power transmitted by the power bus bar VBUS (ie, the power 111 provided by the electronic device 100) from being transmitted to the detecting end of the detecting circuit 330.

In summary, according to whether the adapter 300 receives the power 31 from the external power supplier 30, the adapter 300 of the embodiment can dynamically change the power supply relationship between the electronic device 100 and the adapter 300. When the adapter 300 receives the power 31 of the external power supply 30, the power 31 of the external power supply 30 can be supplied to the electronic device 100 and the adapter 300. When the adapter 300 does not receive the power 31 of the external power supply 30, the electronic device 100 can supply power to the adapter 300.

6 and FIG. 7 are diagrams illustrating an embodiment of the adapter 300 illustrated in FIG. 5, and A schematic diagram of the operation of the adapter 300 in different situations. In the embodiment shown in FIG. 6 and FIG. 7, the switch circuit 340 is the second switch 341, and the detection circuit 330 includes the first switch 331 and the pull-down resistor 332. The first end of the second switch 341 is coupled to the power bus bar VBUS, and the second end of the second switch 341 is coupled to the second power pin V_chg of the second connector 320. The first end of the first switch 331 is coupled to the identification pin ID_pad of the first connector 310. The second end of the first switch 331 is coupled to a reference voltage (eg, a ground voltage or other fixed voltage). The control end of the first switch 331 is coupled to the second power pin V_chg of the second connector 320. The first end and the second end of the pull-down resistor 332 are respectively coupled to the identification pin ID_pad of the first connector 310 and a reference voltage (such as a ground voltage or other fixed voltage). The resistance of the pull-down resistor 332 can be determined according to design requirements. For example, in some embodiments, the pull-down resistor 332 may have a resistance of 124 KΩ.

In the embodiment shown in FIG. 6 and FIG. 7, the transmission module 350 can include a third connector 351. The third connector 351 has a third power pin V_dev and second sub-data pins DP_dev, DM_dev. In this embodiment, the second sub-data pins DP_dev and DM_dev of the third connector 351 are differential data pairs. The second sub-data pins DP_dev and DM_dev of the third connector 351 are coupled to the second data pin D_dev of the transmission module 350, and are respectively coupled to the first data pin D_pad of the first connector 310. A sub data pin DM_pad, DP_pad. In this embodiment, the first sub-data pins DM_pad and DP_pad of the first data pin D_pad are differential data pairs. The first sub-data pins DM_pad and DP_pad are differential data pairs. The first data pin of the first connector 310 shown in FIG. 5 can be referred to. Description of D_pad. In other embodiments, the second data pin D_dev of the third connector 351 and the first data pin D_pad of the first connector 310 may be changed to a single-ended data pin. The third power pin V_dev of the third connector 351 is coupled to the power pin of the transmission module 350, and is coupled to the power bus line VBUS.

The third connector 351 is selectively connectable to a peripheral device of the electronic device 100. For example, FIG. 8 and FIG. 9 are schematic diagrams illustrating different scenarios in which the adapter 300 is plugged into the electronic device 100 according to another embodiment of the present invention. The electronic device 100, the adapter 300, and the external power supplier 30 shown in FIG. 8 and FIG. 9 can be referred to the related description of the electronic device 100, the adapter 300, and the external power supplier 30 of FIGS. 3 and 4. The user can selectively insert the connector 41 of the peripheral device 40 of the electronic device 100 into the third connector 351 of the adapter 300, or selectively connect the connector 41 of the peripheral device 40 from the adapter 300. The three connectors 351 are pulled out. The peripheral device 40 can be a USB flash drive, a mouse, a keyboard, or other peripheral device. When the connector 41 of the peripheral device 40 is inserted into the third connector 351 of the adapter 300, and the first connector 310 of the adapter 300 is inserted into the connector 110 of the electronic device 100, between the peripheral device 40 and the electronic device 100 The data 112 can be transferred to each other via the adapter 300.

Referring to FIG. 6 and FIG. 8 , when the second connector 320 of the adapter 300 is electrically connected to the external power supplier 30 , that is, when the second power pin V_chg of the second connector 320 receives the external power supplier 30 . When the power is 31, the second power pin V_chg outputs the first switch signal and the second switch signal to the detection end of the detection circuit 330 and the second end of the switch circuit 340. The first switch signal causes the detection circuit 330 to be in an off state, and the identification pin ID_pad is based on the detection circuit 330. In the stop state, the identification pin ID_pad transmits a stop transmission signal to the connector 110 of the electronic device 100 according to the off state. The second switch signal causes the switch circuit 340 to be in an on state, and the external power supply 30 output power 31 is transmitted to the power bus bar VBUS via the second power pin V_chg and the switch circuit 340, and the power bus bar VBUS transmits the power 31 to the power bus 31. The first power pin V_pad and the third power pin V_dev of the third connector 351. For example, the power 31 can turn off the first switch 331 of the detection circuit 330 such that the identification pin ID_pad of the first connector 310 is coupled to the reference voltage via the pull-down resistor 332 (eg, ground voltage or other fixed Voltage). Therefore, the power operation mode of the controller (not shown) of the connector 110 of the electronic device 100 is set to the auxiliary charging adapter (ACA) mode. In the ACA mode, the electronic device 100 may receive externally supplied power via the connector 110. For the switch circuit 340, the power 31 can be turned on the second switch 341 of the switch circuit 340 such that the power 31 of the external power supply 30 can pass through the second power pin V_chg of the second connector 320 and the second The switch 341 is transmitted to the power bus bar VBUS. The power of the power bus bar VBUS (at this time, the power 31 supplied from the external power supplier 30) can be transmitted to the connector 41 of the peripheral device 40 via the third power pin V_dev of the third connector 351, and can also be via The first power pin V_pad of the first connector 310 is transmitted to the connector 110 of the electronic device 100.

Referring to FIG. 7 and FIG. 9, when the second power pin V_chg of the second connector 320 of the adapter 300 does not receive the power 31 of the external power supply 30, the second power pin V_chg is a logic low voltage. And the first of the detection circuit 330 The switch 331 is turned on, so that the identification pin ID_pad of the first connector 310 is directly coupled to a reference voltage (such as a ground voltage or other fixed voltage). Therefore, the power operation mode of the controller (not shown) of the connector 110 of the electronic device 100 is set to the line-and-run (OTG) mode. In the OTG mode, the electronic device 100 can supply the power 111 to the power bus bar VBUS of the adapter 300 via the connector 110. For the switch circuit 340, the second switch 341 of the switch circuit 340 is turned off because the second power pin V_chg does not receive the power 31 of the external power supply 30. The second switch 341 of the off state can prevent the power 111 supplied from the electronic device 100 from being transmitted to the control end of the first switch 331 of the detecting circuit 330. The power of the power bus bar VBUS (at this time, the power 111 supplied from the electronic device 100) can be transmitted to the connector 41 of the peripheral device 40 via the third power pin V_dev of the third connector 351.

In summary, the adapter 300 of the embodiment can simultaneously plug the external power supply 30 and the peripheral device 40. According to whether the adapter 300 receives the power 31 of the external power supplier 30, the adapter 300 of the embodiment can dynamically change the power supply relationship between the electronic device 100 and the adapter 300. When the adapter 300 receives the power 31 of the external power supply 30, the power 31 of the external power supply 30 can be simultaneously powered to the electronic device 100 and the peripheral device 40 via the adapter 300. When the adapter 300 does not receive the power 31 of the external power supply 30, the electronic device 100 can supply power to the peripheral device 40 via the adapter 300.

FIG. 10 is a block diagram showing the circuit of the adapter 300 shown in FIGS. 8 and 9 according to another embodiment of the present invention. The embodiment shown in FIG. 10 can refer to FIG. 5 and FIG. 6 . Similar to the description of FIG. 7 and the like. In the embodiment shown in FIG. 10, the detection circuit 330 includes a first sub-switch 333, a second sub-switch 334, and a pull-down resistor 335. The pull-down resistor 335 shown in FIG. 10 can be referred to the related description of the pull-down resistor 332 shown in FIG. 6 and FIG. The first end of the first sub-switch 333 is coupled to the identification pin ID_pad of the first connector 310. The second end of the first sub-switch 333 is coupled to a reference voltage (eg, a ground voltage or other fixed voltage). The control end of the first sub-switch 333 is coupled to the second power pin V_chg of the second connector 320. The first end of the second sub-switch 334 is coupled to the identification pin ID_pad of the first connector 310. The first end of the pull-down resistor 335 is coupled to the second end of the second sub-switch 334, and the second end of the pull-down resistor 335 is coupled to a reference voltage (eg, a ground voltage or other fixed voltage).

The first sub-switch 333 and the second sub-switch 334 described above can be implemented in any form of switching circuit/element. For example, the first sub-switch 333 and/or the second sub-switch 334 may include a transistor, a transfer gate, a relay, or other switching circuit/component. In the embodiment shown in FIG. 10, the second sub-switch 334 includes a Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET), and the first sub-switch 333 includes a resistor 1011 and Solid State Relay (SSR) 1012. The resistance of the resistor 1011 can be determined according to design requirements. For example, in some embodiments, the resistance of resistor 1011 may be 1.8 KΩ. The first end of the resistor 1011 is coupled to the second power pin V_chg of the second connector 320. The first trigger end and the second trigger end of the solid state relay 1012 are respectively coupled to the second end of the resistor 1011 and a reference voltage (such as a ground voltage or other fixed voltage). The first opening of the solid state relay 1012 The closing end and the second switching end are respectively coupled to the identification pin ID_pad of the first connector 310 and a reference voltage (such as a ground voltage or other fixed voltage).

When the second power pin V_chg of the second connector 320 receives the power 31 of the external power supplier 30, the power 31 can drive the solid state relay 1012 via the resistor 1011 to make the first switch end and the second switch end of the solid state relay 1012 The connection state between them is the cutoff state. When the second power pin V_chg of the second connector 320 of the adapter 300 does not receive the power 31 of the external power supply 30, the connection state between the first switch end and the second switch end of the solid state relay 1012 is The conduction state is such that the identification pin ID_pad of the first connector 310 is directly coupled to a reference voltage (eg, a ground voltage or other fixed voltage).

In the embodiment shown in FIG. 10, the switch circuit 340 includes a first P-type transistor 1021, a second P-type transistor 1022, a first capacitor 1023, a first resistor 1024, a second resistor 1025, an N-type transistor 1026, and Control circuit 1030. The first P-type transistor 1021 and the second P-type transistor 1022 may be P-channel MOSFETs, and the N-type transistor 1026 may be an N-channel MOSFET. The first end of the first P-type transistor 1021 is coupled to the power bus bar VBUS. The first end of the second P-type transistor 1022 is coupled to the second end of the first P-type transistor 1021. The second end of the second P-type transistor 1022 is coupled to the second power pin V_chg of the second connector 320. The first end of the first capacitor 1023 and the first end of the first resistor 1024 are coupled to the second end of the first P-type transistor 1021 and the first end of the second P-type transistor 1022.

The first end of the second resistor 1025 is coupled to the control end of the first P-type transistor 1021, the control end of the second P-type transistor 1022, and the second end of the first capacitor 1023. The end is connected to the second end of the first resistor 1024. The first end of the second resistor 1025 is also coupled to the control end of the second sub-switch 334 of the detecting circuit 330. The first end of the N-type transistor 1026 is coupled to the second end of the second resistor 1025. The second end of the N-type transistor 1026 is coupled to a reference voltage (eg, a ground voltage or other fixed voltage). The control circuit 1030 is coupled to the control terminal of the N-type transistor 1026.

The control circuit 1030 correspondingly controls the N-type transistor 1026 according to the voltage of the second power pin V_chg of the second connector 320. For example, when the second power pin V_chg of the second connector 320 receives the power 31 of the external power supply 30, the control circuit 1030 can turn on the N-type transistor 1026. The conduction of the N-type transistor 1026 can pull down the control terminal voltages of the first P-type transistor 1021, the second P-type transistor 1022 and the second sub-switch 334, thereby making the first P-type transistor 1021 and the second P-type The crystal 1022 is electrically connected to the second sub-switch 334. The conduction of the second sub-switch 334 can cause the identification pin ID_pad of the first connector 310 to be coupled to a reference voltage (such as a ground voltage or other fixed voltage) via the pull-down resistor 335, thereby controlling the connector 110 of the electronic device 100. The power operation mode of the device (not shown) is set to the auxiliary charging adapter (ACA) mode. In the ACA mode, the electronic device 100 may receive externally supplied power via the connector 110. The conduction of the first P-type transistor 1021 and the second P-type transistor 1022 can cause the power of the second power pin V_chg of the second connector 320 (at this time, the power 31 of the external power supplier 30) to be transmitted to the power. Bus bar VBUS. The power of the power bus bar VBUS (in this case, the power 31 supplied by the external power supplier 30) can be transmitted to the peripheral device via the third power pin V_dev of the third connector 351, and can also be connected via the first connection. The first power pin V_pad of the device 310 is transmitted to the electronic device 100.

When the second power pin V_chg of the second connector 320 of the adapter 300 does not receive the power 31 of the external power supply 30, the control circuit 1030 can turn off the N-type transistor 1026. During the period in which the N-type transistor 1026 is turned off, the control terminal voltages of the first P-type transistor 1021, the second P-type transistor 1022, and the second sub-switch 334 are pulled high by the resistor 1024, thereby causing the first P-type transistor. 1021. The second P-type transistor 1022 and the second sub-switch 334 are turned off. On the other hand, the solid state relay 1012 of the detecting circuit 330 directly couples the identification pin ID_pad of the first connector 310 to a reference voltage (for example, a ground voltage or other fixed voltage), so that the connector 110 of the electronic device 100 is controlled. The power operation mode of the device (not shown) is set to the line-and-run (OTG) mode. In the OTG mode, the electronic device 100 can supply the power 111 to the power bus bar VBUS of the adapter 300 via the connector 110. The cut-off first P-type transistor 1021 and the second P-type transistor 1022 can prevent the power 111 supplied from the electronic device 100 from being transmitted to the control end of the switch 333 of the detecting circuit 330. The power of the power bus bar VBUS (at this time, the power 111 supplied from the electronic device 100) can be transmitted to the peripheral device via the third power pin V_dev of the third connector 351.

Control circuit 1030 can be implemented in any manner. For example, in the embodiment shown in FIG. 10, the control circuit 1030 includes a third resistor 1031, a fourth resistor 1032, a fifth resistor 1033, a sixth resistor 1034, a second capacitor 1035, an operational amplifier 1036, and a seventh resistor 1037. The eighth resistor 1038 and the third capacitor 1039. The first ends of the resistors 1031 and 1033 are coupled to the second power pin of the second connector 320 V_chg. The first end and the second end of the fourth resistor 1032 are respectively coupled to the second end of the third resistor 1031 and a reference voltage (such as a ground voltage or other fixed voltage). The first end and the second end of the sixth resistor 1034 are respectively coupled to the second end of the fifth resistor 1033 and a reference voltage (such as a ground voltage or other fixed voltage). The first end and the second end of the second capacitor 1035 are respectively coupled to the second end of the fifth resistor 1033 and a reference voltage (such as a ground voltage or other fixed voltage). The resistance of the resistors 1031, 1032, 1033, 1034 can be determined according to design requirements. In some embodiments, the resistance ratio of the resistors 1031 and 1032 may be 3:2 (but not limited thereto), and the resistance ratio of the resistors 1033 and 1034 may be 1:1 (but not limited thereto). . For example, the resistance of the third resistor 1031 may be 3KΩ, the resistance of the fourth resistor 1032 may be 2KΩ, and the resistance of the fifth resistor 1033 and the sixth resistor 1034 may be 100KΩ.

The first input terminal (eg, the inverting input terminal) of the operational amplifier 1036 is coupled to the second terminal of the third resistor 1031. A second input of the operational amplifier 1036 (eg, a non-inverting input) is coupled to the second end of the fifth resistor 1033. When the voltage of the second power pin V_chg of the second connector 320 is maintained at a steady state, since the voltage of the inverting input terminal of the operational amplifier 1036 is smaller than the voltage of the non-inverting input terminal, the output terminal of the operational amplifier 1036 outputs a logic high voltage. .

When the voltage of the second power pin V_chg of the second connector 320 rises from 0V, the second capacitor 1035 increases the transient response time of the voltage of the non-inverting input of the operational amplifier 1036. That is, when the voltage of the second power pin V_chg rises, the voltage rising speed of the non-inverting input terminal of the operational amplifier 1036 is slower than the inverting input terminal of the operational amplifier 1036 because of the influence of the second capacitor 1035. The rate of voltage rise. Therefore, after the voltage of the second power pin V_chg rises and is delayed for a while, the voltage at the output of the operational amplifier 1036 is converted from a logic low voltage to a logic high voltage. The capacitance value of the second capacitor 1035 can be determined according to design requirements. For example, in some embodiments, the capacitance value of the second capacitor 1035 may be 10 μF. In the transient response time of the voltage at the non-inverting input of the operational amplifier 1036, since the voltage at the inverting input of the operational amplifier 1036 is greater than the voltage at the non-inverting input, the output of the operational amplifier 1036 temporarily outputs a logic low voltage. . After the transient response time of the voltage at the non-inverting input of operational amplifier 1036, the output of operational amplifier 1036 returns to a logic high voltage since the voltage at the inverting input of operational amplifier 1036 is less than the voltage at the non-inverting input.

The second power pin V_chg of the second connector 320 is supplied to the operational amplifier 1036. When the second power pin V_chg of the second connector 320 does not receive the power 31 of the external power supply 30, the operational amplifier 1036 loses power and is disabled, causing the voltage at the output of the operational amplifier 1036 to be a logic low voltage.

The first end of the seventh resistor 1037 is coupled to the output of the operational amplifier 1036. The second end of the seventh resistor 1037 is coupled to the control end of the N-type transistor 1026. The first end of the eighth resistor 1038 is coupled to the second end of the seventh resistor 1037. The second end of the eighth resistor 1038 is coupled to a reference voltage (eg, a ground voltage or other fixed voltage). The first end of the third capacitor 1039 is coupled to the second end of the seventh resistor 1037. The second end of the third capacitor 1039 is coupled to a reference voltage (eg, a ground voltage or other fixed voltage). The resistance of the resistors 1037, 1038 and the capacitance of the third capacitor 1039 can be determined according to design requirements. For example, in some embodiments, the resistor 1037 is The resistance of 1038 may be 10KΩ, while the capacitance of the third capacitor 1039 may be 4.7μF.

FIG. 11 is a block diagram showing the circuit of the adapter 300 shown in FIGS. 8 and 9 according to still another embodiment of the present invention. The embodiment shown in FIG. 11 can be analogized with reference to the related descriptions of FIGS. 5, 6, and 7. In the embodiment shown in FIG. 11, the detection circuit 330 includes a first switch 331. The first end of the first switch 331 is coupled to the identification pin ID_pad of the first connector 310. The second end of the first switch 331 is coupled to a reference voltage (eg, a ground voltage or other fixed voltage). The control end of the first switch 331 is coupled to the second power pin V_chg of the second connector 320. The adapter 300 further includes a clamp circuit 1100. The clamp circuit 1100 is coupled to the first sub-data pin DM_pad of the first connector 310. During an initial period in which the second power pin V_chg of the second connector 320 receives the power 31 of the external power supplier 30, the clamp circuit 1100 maintains the potential of the first sub-data pin DM_pad of the first connector 310 at the first time. Potential (eg 0.6V).

When the second power pin V_chg of the second connector 320 receives the power 31 of the external power supplier 30, the power 31 may turn off the first switch 331 of the detecting circuit 330. At the same time, the clamp circuit 1100 maintains the potential of the first sub-data pin DM_pad of the first connector 310 at a first potential (for example, 0.6 V). Therefore, the power operation mode of the controller (not shown) of the connector 110 of the electronic device 100 coupled to the first connector 310 is set to a Charging Downstream Port (CDP) mode.

Clamp circuit 1100 can be implemented in any manner. For example, FIG. 12 is a circuit block diagram showing the clamp circuit 1100 of FIG. 11 according to an embodiment of the invention. intention. In the embodiment shown in FIG. 12, the clamp circuit 1100 includes a resistor 1101 and a resistor 1102. The first end of the resistor 1101 is coupled to the power bus bar VBUS. The second end of the resistor 1101 and the first end of the resistor 1102 are coupled to the first sub-data pin DM_pad of the first data pin D_pad of the first connector 310. The second end of the resistor 1102 is coupled to a reference voltage (eg, a ground voltage or other fixed voltage). The resistance values of the resistors 1101 and 1102 can be determined according to design requirements. The voltage of the power bus bar VBUS is divided by the resistors 1101 and 1102 such that the potential of the first sub-data pin DM_pad of the first connector 310 is maintained at the first potential (for example, 0.6 V).

Referring to FIG. 11, when the second power pin V_chg of the second connector 320 of the adapter 300 does not receive the power 31 of the external power supply 30, the second power pin V_chg is detected as a logic low voltage. The first switch 331 of the measuring circuit 330 is turned on, so that the identification pin ID_pad of the first connector 310 is directly coupled to a reference voltage (for example, a ground voltage or other fixed voltage). Therefore, the power operation mode of the controller (not shown) of the connector 110 of the electronic device 100 is set to the line-and-run (OTG) mode. In the OTG mode, the electronic device 100 can supply the power 111 to the power bus bar VBUS of the adapter 300 via the connector 110. For the switch circuit 340, when the second power pin V_chg of the second connector 320 of the adapter 300 does not receive the power 31 of the external power supplier 30, the second switch 341 of the switch circuit 340 is in an off state. The second switch 341 of the off state can prevent the power 111 supplied from the electronic device 100 from being transmitted to the control end of the first switch 331 of the detecting circuit 330. The power of the power bus bar VBUS (at this time, the power 111 provided by the electronic device 100) may be via the third power pin of the third connector 351. V_dev is transmitted to the peripheral device.

In summary, the adapter 300 of the embodiment can simultaneously plug the external power supply and the peripheral device. The adapter 300 of the present embodiment can dynamically change the power supply relationship between the electronic device 100 and the adapter 300 according to whether the adapter 300 receives power from the external power supply. When the adapter 300 receives the power 31 of the external power supply 30, the adapter 300 can trigger the electronic device 100 such that the power operation mode of the controller (not shown) of the connector 110 is set to be charged down. (CDP) mode. Therefore, the power 31 of the external power supplier 30 can be simultaneously supplied to the electronic device 100 and the peripheral device 40 via the adapter 300. When the adapter 300 does not receive the power 31 of the external power supply 30, the adapter 300 can trigger the electronic device 100 such that the power operation mode of the controller (not shown) of the connector 110 is set to be wired. Ie running (OTG) mode. Therefore, the electronic device 100 can be powered to the peripheral device 40 via the adapter 300.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present invention, and any one of ordinary skill in the art can make some changes and refinements without departing from the spirit and scope of the present invention. The scope of the invention is defined by the scope of the appended claims.

300‧‧‧Adapter

310‧‧‧First connector

320‧‧‧Second connector

330‧‧‧Detection circuit

340‧‧‧Switch circuit

350‧‧‧Transmission module

D_dev‧‧‧Second data pin

D_pad‧‧‧ data pin

ID_pad‧‧‧ID pin

V_chg‧‧‧second power pin

V_pad‧‧‧First power pin

VBUS‧‧‧Power Bus

Claims (13)

An adapter for an electronic device, the adapter comprising: a first connector having a first power pin and an identification pin, wherein the first connector is selectively electrically connectable a connector of the electronic device; a power bus bar coupled to the first power pin; a second connector having a second power pin, wherein the second connector is selectively electrically connectable to an external a power supply device, when the second connector is electrically connected to the external power supply, the second power pin outputs a first switch signal and a second switch signal; and a transmission module has a third power connection The switch is coupled to the power bus; the switch circuit includes a first end and a second end, and the first end and the second end are respectively coupled to the power bus and the second power pin, The second end is capable of receiving the second switch signal output by the second power pin to make the switch circuit be in an on state, and the external power supply outputting a power is transmitted to the second power pin and the switch circuit to The power bus and can pass through The power bus transmits the power to the first power pin and the third power pin; and a detecting circuit includes an output end and a detecting end, and the output end is coupled to the detecting end Up to the identification pin and the second power pin, the detecting end can receive the first switch signal output by the second power pin to make the detecting circuit be in an off state, when the first connector is electrically When the connector of the electronic device is connected and the second connector is electrically connected to the external power supply, the identification pin transmits a power transmission stop signal to the connector of the electronic device according to the off state. The adapter of claim 1, wherein the electronic device When the connector receives the stop power transmission signal transmitted by the identification pin, the connector of the portable electronic device changes a power operation mode of a controller of the connector of the electronic device according to the stop power transmission signal. The adapter of claim 2, wherein the connector of the electronic device is a universal serial bus bar connector, and the controller of the connector is a universal serial bus bar controller. The adapter of claim 2, wherein a connection state between the first end and the second end of the switch circuit when the second connector is not electrically connected to the external power supply For the off state, the detection circuit is in an on state, and the power operation mode of the controller of the connector of the electronic device is a connected mode. The adapter of claim 4, wherein when the second connector is electrically connected to the external power supply, the connection state between the first end and the second end of the switch circuit is In the conducting state, the detecting circuit is in an off state, the connector of the electronic device receives the stop power transmission signal transmitted by the identification pin, so that the connector operates the power operation mode of the controller according to the stop power transmission signal The operation mode is changed from the connection mode to an auxiliary charging adapter mode. The adapter of claim 1, wherein the detecting circuit further comprises: a first switch, a first end of which is coupled to the identification pin of the first connector, the first switch A second end is coupled to a reference voltage, and a control end of the first switch is coupled to the second power pin of the second connector. The adapter of claim 6, wherein the detecting circuit further comprises: a pull-up resistor, wherein a first end and a second end are respectively coupled to the identification pin of the first connector With this reference voltage. The adapter of claim 1, wherein the switch circuit is a second switch, the first end of which is coupled to the power bus, and the second end of the second switch and a control end are coupled Connected to the second power pin of the second connector. The adapter of claim 1, wherein the switch circuit comprises: a first P-type transistor, a first end of the first P-type transistor is coupled to the power bus; a P-type transistor, a first end of the second P-type transistor is coupled to a second end of the first P-type transistor, and a second end of the second P-type transistor is coupled to a second power pin of the second connector; a first capacitor coupled to the second end of the first P-type transistor and the first end of the second P-type transistor The second end of the first capacitor is coupled to the control end of the first P-type transistor and the control end of the second P-type transistor; a first resistor coupled to the first end of the first resistor The second end of the P-type transistor is coupled to the first end of the second P-type transistor, and the second end of the first resistor is coupled to the control end of the first P-type transistor and the first end a control terminal of the second P-type transistor; a second resistor coupled to the second end of the first resistor; an N-type transistor having a first end coupled to the second a second end of the resistor, A second end of the N-type transistor is coupled to a reference voltage; and a control circuit is coupled to a control end of the N-type transistor, wherein the control circuit is configured according to the second power of the second connector The voltage of the pin is used to control the N-type transistor. The adapter of claim 9, wherein the detecting circuit comprises: a first sub-switch, a first end of which is coupled to the identification pin of the first connector, the first sub- A second end of the switch is coupled to the reference voltage, and a control end of the first sub-switch is coupled to the second power pin of the second connector; a second sub-switch has a first end The first terminal of the second sub-switch is coupled to the first end of the second resistor; and the pull-up resistor is coupled to the first end and the first The two ends are respectively coupled to a second end of the second sub-switch and the reference voltage. The adapter of claim 9, wherein the control circuit comprises: a third resistor having a first end coupled to the second power pin; a fourth resistor having a first end And a second end coupled to the second end of the third resistor and the reference voltage; a fifth resistor having a first end coupled to the second power pin; a sixth resistor, one of the first The first end and the second end are respectively coupled to a second end of the fifth resistor and the reference voltage; a second capacitor, a first end and a second end are respectively coupled to a second end of the fifth resistor and the reference voltage; an operational amplifier, a first input end and a second input end respectively a second end of the third resistor and a second end of the fifth resistor; a seventh resistor, a first end and a second end are respectively coupled to an output end of the operational amplifier The control terminal of the N-type transistor; an eighth resistor, a first end and a second end are respectively coupled to the second end of the seventh resistor and the reference voltage; and a third capacitor A first end and a second end are respectively coupled to the second end of the seventh resistor and the reference voltage. The adapter of claim 1, wherein the first connector further comprises a first data pin, and the transmission module further comprises: a third connector having the third power pin And the second data pin of the third connector is coupled to the power bus, the second data pin of the third connector is coupled to the first connector The first data pin, wherein the third connector is selectively electrically connectable to a peripheral device of the electronic device. The adapter of claim 12, further comprising: a clamp circuit coupled to the first data pin of the first connector, wherein the second connector receives the external power supply The clamp circuit maintains the potential of the first data pin of the first connector at a first potential during an initial period of the power of the device.